The invention relates to an underwater bin-filling plant.
Plants of the kind in object are used in harvest collection and sorting centres. The fruit worked in such plants are generally constituted by apples, oranges and similar.
In fruit collection centres, the fruit arriving from the fields is tipped on to sorting lines on which the fruit is selected according to size and characteristics, unsuitable fruit being eliminated. Then fruit of one type (of the same size) is placed in large bins in order to be sent for distribution or conservation.
In the collection centres, the fruit is transported by means of transport channels on which the fruit floats and is carried to a removal zone; these plants generally have a considerable number of transport channels, each of which conveys fruit of different characteristics which are to be placed in different bins.
In the prior art, a bell is envisaged at the removal area, which bell's open end is immersed in water; under the bell there is an empty bin which is also immersed in water. Using transport means of known type and generally constituted by bucket conveyors or the like, the fruit is removed at the removal zone and conveyed downwards below the free surface of the water, and inserted, still under water, inside the bell. The fruit floats in the water contained in the bell; once there is the desired quantity of fruit inside the bell, the bin positioned under the bell is raised and in its upcoming movement raises also the bell; when the bin has emerged from the water, the bell, which at this point is above the bin, unloads its fruits into the bin. By means of pushing means the bin, unhindered by the bell, which is held up by special hooks, is substituted with an empty bin. The empty bin is hooked to the bell and the entirety is re-immersed in the water ready for a new filling phase.
In prior art plants, with the aim of preventing the fruit transport means from interfering with the bin or with the bell wall, the bells are inferiorly equipped with a one-way "Clapet" hatch that opens during the insertion phase of the fruit into the bell and closes during the raising phase of the bell. Further, to permit the introduction of a considerable quantity of fruit into the bell, the bell itself must be immersed up to a considerable depth in the water; this brings about the need to bore deeply into the factory floor at the part where the bell is located, so as to enable the bin to be contained when it is in the completely lowered position. Instead of boring deep holes in the floor, the problem is often solved by raising the entire removal zone. This however leads to considerable complications during the construction of the plant. In prior art plants, even if several conveyor channels arrive at the removal zone, which on command unload their fruit which is then directed under the bell, it is still necessary to provide several bells and several feeding systems for the bins; this obviously leads to an increase in the costs of the plant itself.